Suspension for electric-lighting fixtures



' L. ERIKSON SUSPENSION FOR ELECTRIC LIGHTING FIXTURES F'ild May 2, 1923 Patented Aug. 25, 1925.

UNITED STATES PATENT OFFICE.

LEONARD ERIKSON, 0F MALDEN, MASSACHUSETTS.

SUSPENSION FOR ELECTRIC-LIGHTING FIXTURES.

Application filed May 2,

To all whom it may concern:

Be it known that I, LEONARD ERIKSON, acitizen of the United States, and a resident of Malden, in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Suspensions for Electric-Lighting Fixtures, of which the following is a specification.

My invention relates to suspensions for electric lighting fixtures and its object is to provide such suspension which shall be light in weight, but at the same time sufiiciently strong to sustain heavy fixtures, which shall be simple in construction and economical to manufacture, and by means of which the electrical conductor passing from the ceiling box to the lamp or lamps shall be completely hidden from view.

I'Vith the foregoing objects in view my invention involves a suspension of the chain type formed of hollow tubular links provided with registering openings through which the electrical conductor passes from the ceiling box to the lamp or lamps, and preferably the hollow links which make up the chain are divided longitudinally to form identical sections, means being provided for positively securing said sections together, such means preferably lying in the longitudinal axis of the chain, and for interlocking each cooperating pair of links.

In the preferred form of my invention each section has a lug at one end and a depression and a lug at the other so that the lug at the end of one section will fit into the depression and over the lug of the other, suitable attaching means such as screws, pins, or rivets, passing through said lugs for uniting the sections. The registering openings in the links are formed in the inner surfaces of the end portions thereof, and preferably, the edges of the metal at said openings are notched or indented, so as more efiectively to prevent such spreading of the sections and also tolock each pair of links together.

One embodiment of my invention is shown in the accompanying drawings in which- Figure 1 is an elevation of a suspension for electric lighting fixtures embodying my invention;

Fig. 2 is a central longitudinal section of a link and one of the links cooperating therewith Fig. 3 is a plan View of a link before 1923. Serial No. 636,043.

the sections thereof have been secured together.

In the particular drawings selected for more fully disclosing my invention, 10 represents a hollow fixed support herein shown as a ring threaded at its upper portion to the usual pipe 11 which enters and is held by the ceiling box (not shown), said pipe being enclosed within the usual canopy l2.

Suspended from the ring 10 is a chain formed of hollow links, 13, 14, each link being formed of two longitudinal sections 15, 16 which for cheapness of manufacture preferably are identical and may convenipntly be stamped out of blanks by suitable CleS.

While various means may be employed for securing the two sections of a link together, I prefer, as shown in the present instance, to provide one end of each section with a laterally projecting lug 17, herein shown as semi-circular in form, and the other end with a depression 18 and a semi-circular lug 19 having its upper surface in the same plane as said depression and arranged as shown in Fig. 2 to fit under the lug 17 so that when the latter is placed in the depression 18, the upper surface of the section 15 will be flush with that of the section 16. The lugs are provided with apertures through which screws 20, or any other suitable securing means, may pass in order to connect the two sections, and the axes of such connecting means preferably lie in the longitudinal axis of the chain to increase the strength thereof. I

Each link has oppositelydisposed openings 21, 22 in the inner surfaces of the end portions thereof, which openings register, respectively, with the corresponding openings in the inner surfaces of the adjacent links.

In like manner the inner surface of the lower portion of the ring 10 is provided with an opening 23 which registers with the opening in the upper portion of the topmost link 13.

After the chain has been assembled, the wires 24 which pass from the ceiling box through the pipe 11 to the fixed ceiling ring 10 are threaded through the opening 23 in said ring and thence through the opening 21 in the first link through which link said wires pass to the opening 22 in the lower portion thereof, whereupon they are drawn out of said link and into and through the next link 14, and so on until the entire chain is wired, and the ends of the conductors are electrically connected to the lamp or lamps.

As shown in Fig. 2 the edges of the metal at the registering openings formed in the inner surfaces of the end portions of the links are notched or indented so as to more efiectively to prevent the spreading of the sections by the weight carried by the chain, and also to lock each pair of links together. By means of this construction any tendency of the Weight of the fixture to exert a side thrust on the sections of the links is eliminated, and the force is exerted through the longitudinal axis of the same.

l/Vhile notches or indentations of various forms and shapes may be employed, I have found that notches or indentations of the shape shown in Fig. 2 are well suited for my pur ose.

e notches 25 are formed with their outer sides 26 substantially parallel to the longitudinal axis of the link, and their other sit e'- 27 disposed angularly to said axis so that when the chain is assembled, the inclined edges of the notches of a pair of links will come together, the point 28 of each link extending beyond the side of the other and exteriorly thereof. By means of this arrangement all tendency to spreading is eliminated, the thrust being downward, and links are effectively interlocked.

Preferably a second notch 29 is formed at the juncture of the sections of each link for the purpose of permitting the conductors 2% more readily to pass from one link to the other.

By making the link sections identical in shape so that they may both be stamped out of blanks by one set of dies, the cost of manufacture is materially reduced and the work of assembly is simplified.

By following the directions above given, a chain may be made of comparatively light stock which will be capable of supporting the heaviest-type, of fixtures, for example, fixtures weighing'=several hundred pounds, and by virtue of the concealment of the electrical conductors, the appearance of the ighting system is greatly improved.

laying thus described an illustrative embodiment of my invention without however limiting the same thereto, what 1 claim and dc ire to secure by Letters Patent is .1 suspension for electric lighting fixtures comprising a chain formed of hollow tubular links, each link being divided longitudi naiiy to form two identical sections and having oppositely disposed openings in the inner siiriaces of the end portions thereof, the edges of said openings in each link being notched to receive the corresponding notches of the co-operating link whereby each pair of links is interlocked, and means independent of said sections for securing the same together.

In testimony whereof, I have hereunto subscribed my name this first day of May, 1923.

LEONARD ERIKSON. 

